Brismar, Hjalmar

Hedin, Niklas

Bergström, Lennart

Abstract [en]

The transport of oligomeric molecules in silica spheres with cylindrical mesopores has been quantified and related to
the structural features of the spherical particles and the interactions at the solid-liquid interface. An emulsion-solvent
evaporation method was used to produce silica spheres having cylindrical mesopores with an average pore diameter of
6.5 nm. The transport of dextran molecules (fluorescently tagged) with molecular weights of 3000 and 10 000 g/mol was
quantified using confocal laser scanning microscopy (CLSM). The intraparticle concentration profiles in the dextrancontaining
spheres were flat at all times, suggesting that the release is not isotropic and not limited by diffusion. The
release of dextran into the solution is characterized by an initial burst, followed by long-term sustained release. The
release follows a logarithmic time dependency, which was rationalized by coupling concentration-dependent effective
diffusion constants with adsorption/desorption.

Place, publisher, year, edition, pages

2010. Vol. 26, no 1, 466-470 p.

Keyword [en]

Intraparticle transport and release of dextran in silica spheres with cylindrical mesopores